best method for "rigging" a vehicular model


I moved to Unreal Engine 4 from Unity, and I have quite a hard time adjusting currently. Seems like many things that were easy to do in Unity are just that much harder to achieve in Unreal (might be me though)

I am currently trying to import a vhicular model I created for Unity long time ago and I rebaked for use with Unreal.

My process in Unity originally was to crete a multipart models (with wheels, turret, guns being their own separate meshes), adjust the pivot point to where the parts should have their pivot axes and import that as a multi-object .obj file. Every Mesh got imported into its own sub gameobject within the obj gameobject, and was still fully rotatale and translatable, with the gameobject origin at the pivot point of the mesh.
then I would animate the parts from script. Worked brilliantly, was easy to do.

The only real problem of course was the draw calls disaster that happened because of the different meshes being involved. I found a solution to that thanks to the aset store, an engine tool that would bake a rigged mesh out of multipart mesh, automatically creating an armature so that the bones would correspond to the origins uf the submeshes. Worked 100%, gave me a mesh that was still fully posable, but reduced the drawcalls drastically.

Now I see 1) Unreal will not import fbx or obj files with leaving the parenting intact, but as separate static meshes (meaning I would need to assemble the multipart model in the engine editor, good luck with that), and 2) creating the armature in Blender looks like a longwinding process compared to just adjusting the pivot points of the submeshes before combining them.

Is there any easy (er) way of creating a rigged mesh for a vehicle out of the original multipart one that I am not aware of? I would love to have that engine tool for Unreal that I used in Unity, it made my life so much easier… but given that Unreal has nowhere near the 3rd party tools yet that Unity does, is there any way to emulate that in Blender? Some “pivot-points to bones” script that I don’t know about?

How do others rig their vehicles efficiently, especially the parts that need to be superexact (like the bones for the wheels that should end up in the dead center of the wheel)?

Few things that come to mind:

In blender, you can move bones to the dead center of the wheel using 3d cursor snapping.

Select wheel, press Shift+S to bring up snap menu, then Select “Cursor to Selected”.
Then select bone you want to move, press Shift+S to bring up the same menu, select “Selected to Cursor”. That’ll move the cursor into dead center of the wheel.

This way you can move anything to match position of anything else.

Also, you should really look into automatic creation of static mesh sockets during mesh import. That’s because if I were you I’d try to solve the situation via mesh sockets (That would make it possible to assemble the whole car from parts).

Apparently it worked in the past, but might be currently broken.

Funny I was playing with this this weekend. If you do a hierarchy in your DCC (I was using Blender), like


Just parent them. Then save as one FBX. When you import to UE, tick the ‘Import as Skeletal’ button and it will turn it into a rigged single asset for you. (Make sure your pivots are where you want them etc.)